Math Credit Challenge

[bluguerrilla]

lol, brb.

What's the sum of the function f(n,a) = 1/(n^2+a^2) over all n in element of the natural numbers and for any a in element of the complex numbers.

No using math programs.

This is part of my favorite math problem.

Or you could do my favorite problem.

Starting with the geometric series prove that the above sum from 1 -> infinity for a = 0 is equal to pi^2/6 (this doesn't require complex analysis, just creative thinking).